Many machines incorporate a number of working elements, such as pneumatic cylinders, pneumatic motors, vacuum generators, and the like, that require a source of air or other fluid for operation.
A common practice is to mount the valves that control the flow of air to the working elements in a side-by-side stack on a manifold having an air inlet passage that is connected commonly to each of the valves. The outlet passage of each valve is also connected through an outlet in the manifold which in turn is connected via fluid lines to the working elements.
A valve stack arrangement has distinct advantages. As a common manifold is employed to supply and discharge air from the valves, the piping is substantially reduced over a system utilizing individually mounted valves. Further, the valve stack provides a central control location for inspection of the valves.
In the past, the stack of valves has been held together with end plates that trap the individual components and supply air commonly to each valve. However, the removal and replacement of a valve often requires that the entire connecting mechanism including the end plates be disassembled. This is a time consuming task and requires the use of tools.